UTMPX(5) NetBSD File Formats Manual UTMPX(5)
NAMEutmpx, wtmpx, lastlogx -- user accounting database
SYNOPSIS#include <utmpx.h>DESCRIPTION
In contrast to utmp and wtmp, the extended databases in utmpx and wtmpx
reserve more space for logging hostnames, and also information on a
process' ID, termination signal and exit status.
The <utmpx.h> header defines the structures and functions for logging
user. Currently logged in users are tracked in /var/run/utmpx, a list of
all logins and logouts, as well as all shutdowns, reboots and date
changes, is kept in /var/log/wtmpx, and the last login of each user is
noted in /var/log/lastlogx.
The interface to the utmpx file is described in getutxent(3).
The wtmpx file can grow rapidly on busy systems, and is normally rotated
with newsyslog(8).
In the event of a date change, a shutdown, or a reboot, the following
items are logged in the wtmpx file:
date The system time has been manually or automatically
updated by date(1). The command name date is recorded
in the field ut_name. In the field ut_line, the char-
acter `|' indicates the time prior to the change, and
the character `{' indicates the new time.
reboot
shutdown A system reboot or shutdown has been initiated. The
character `~' is placed in the field ut_line, and
reboot or shutdown in the field ut_name (see
shutdown(8) and reboot(8)), using logwtmpx(3).
FILES
/var/run/utmpx The utmpx file.
/var/log/wtmpx The wtmpx file.
/var/log/lastlogx The lastlogx file.
SEE ALSOlast(1), login(1), rwho(1), w(1), who(1), endutxent(3), logwtmpx(3),
utmp(5), ac(8), init(8), newsyslog(8), reboot(8)
NetBSD 5.0.1 January 31, 2007 NetBSD 5.0.1

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